flake.lock: Update

Flake lock file changes:

• Updated input 'flake-utils':
    'github:numtide/flake-utils/3cecb5b042f7f209c56ffd8371b2711a290ec797' (2022-02-07)
  → 'github:numtide/flake-utils/a4b154ebbdc88c8498a5c7b01589addc9e9cb678' (2022-04-11)
• Updated input 'nixos-hardware':
    'github:nixos/nixos-hardware/9886a06e4745edb31587d0e9481ad82d35f0d593' (2022-02-04)
  → 'github:nixos/nixos-hardware/6b4ebea9093c997c5f275c820e679108de4871ab' (2022-04-21)
• Updated input 'nixpkgs':
    'github:nixos/nixpkgs/521e4d7d13b09bc0a21976b9d19abd197d4e3b1e' (2022-02-07)
  → 'github:nixos/nixpkgs/9887f024766aa27704d1f89f623efd1d063da92a' (2022-04-21)

flake.lock

@@ -2,11 +2,11 @@
   "nodes": {
     "flake-utils": {
       "locked": {
-        "lastModified": 1644229661,
-        "narHash": "sha256-1YdnJAsNy69bpcjuoKdOYQX0YxZBiCYZo4Twxerqv7k=",
+        "lastModified": 1649676176,
+        "narHash": "sha256-OWKJratjt2RW151VUlJPRALb7OU2S5s+f0vLj4o1bHM=",
         "owner": "numtide",
         "repo": "flake-utils",
-        "rev": "3cecb5b042f7f209c56ffd8371b2711a290ec797",
+        "rev": "a4b154ebbdc88c8498a5c7b01589addc9e9cb678",
         "type": "github"
       },
       "original": {
@@ -38,11 +38,11 @@
     },
     "nixos-hardware": {
       "locked": {
-        "lastModified": 1643980037,
-        "narHash": "sha256-RdVHt2mD408WXMjQIOLvUzy8cSUHu8NAbilDmPVxf7E=",
+        "lastModified": 1650522846,
+        "narHash": "sha256-SxWHXRI3qJwswyXAtzsi6PKVY3KLNNnb072KaJthII8=",
         "owner": "nixos",
         "repo": "nixos-hardware",
-        "rev": "9886a06e4745edb31587d0e9481ad82d35f0d593",
+        "rev": "6b4ebea9093c997c5f275c820e679108de4871ab",
         "type": "github"
       },
       "original": {
@@ -54,11 +54,11 @@
     },
     "nixpkgs": {
       "locked": {
-        "lastModified": 1644193793,
-        "narHash": "sha256-ggCI5LCXwkUJQwjpkr9qDFbQMiK3JvAfeNR4Uy0ny5Q=",
+        "lastModified": 1650501692,
+        "narHash": "sha256-ApKf0/dc0SyB7zZ6yiiOQgcXAhCXxbSDyihHfRDIzx0=",
         "owner": "nixos",
         "repo": "nixpkgs",
-        "rev": "521e4d7d13b09bc0a21976b9d19abd197d4e3b1e",
+        "rev": "9887f024766aa27704d1f89f623efd1d063da92a",
         "type": "github"
       },
       "original": {